1 files changed, 5 insertions, 0 deletions
diff --git a/async.c b/async.c
index 5acd01c..84480bc 100644
--- a/async.c
+++ b/async.c
@@ -650,6 +650,11 @@ int redisvAsyncCommand(redisAsyncContext *ac, redisCallbackFn *fn, void *privdat
     int len;
     int status;
     len = redisvFormatCommand(&cmd,format,ap);
+
+    /* We don't want to pass -1 or -2 to future functions as a length. */
+    if (len < 0)
+        return REDIS_ERR;
+
     status = __redisAsyncCommand(ac,fn,privdata,cmd,len);
     free(cmd);
     return status;